On Monday the bishops said: “We cannot agree that euthanasia is practised on psychiatric patients who are not terminally ill.

“Our point of view does not mean that we want to leave the person in pain. The mental suffering may be immense and a person may find himself totally desperate and without any hope ¬- but it is precisely in this situation that we must remain close to him and not abandon him.

“There is, in fact, a limit and a prohibition that have been in force for so long, since the origins of men living together,” they said. “If we touch it, we are attacking the very foundations of our civilisation.

“That’s the reason why we call for great restraint and continuing dialogue on these issues,” the bishops said.

The bishops also expressed their “deep appreciation” for those who helped care for psychiatric patients. The Brothers of Charity run 15 psychiatric centres in the country which care for more than 5,000 patients a year.